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#ifndef DOUBLE_CONVERSION_CACHED_POWERS_H_
#define DOUBLE_CONVERSION_CACHED_POWERS_H_

#include "diy-fp.h"

namespace WTF {

namespace double_conversion {
    
    class PowersOfTenCache {
    public:
        
        // Not all powers of ten are cached. The decimal exponent of two neighboring
        // cached numbers will differ by kDecimalExponentDistance.
        static int kDecimalExponentDistance;
        
        static int kMinDecimalExponent;
        static int kMaxDecimalExponent;
        
        // Returns a cached power-of-ten with a binary exponent in the range
        // [min_exponent; max_exponent] (boundaries included).
        static void GetCachedPowerForBinaryExponentRange(int min_exponent,
                                                         int max_exponent,
                                                         DiyFp* power,
                                                         int* decimal_exponent);
        
        // Returns a cached power of ten x ~= 10^k such that
        //   k <= decimal_exponent < k + kCachedPowersDecimalDistance.
        // The given decimal_exponent must satisfy
        //   kMinDecimalExponent <= requested_exponent, and
        //   requested_exponent < kMaxDecimalExponent + kDecimalExponentDistance.
        static void GetCachedPowerForDecimalExponent(int requested_exponent,
                                                     DiyFp* power,
                                                     int* found_exponent);
    };
    
    // Initializes the table of cached powers used by the dtoa algorithm.
    // This needs to be called when JSC is being initialized.
    WTF_EXPORT_PRIVATE void initialize();
    
}  // namespace double_conversion

} // namespace WTF

#endif  // DOUBLE_CONVERSION_CACHED_POWERS_H_
